When Raleigh Water decided to change how it handled biosolids at its Neuse River Resource Recovery Facility, it did so in a big way.
“This is a comprehensive biosolids upgrade project,” says Erika Bailey, P.E., assistant director. “We’re using an advanced process — thermal hydrolysis pretreatment — that preconditions the solids upstream of anaerobic digestion. It makes digestion more efficient. It does a better job of destructing the organic solids, and it produces more biogas.”Previously, the plant in North Carolina’s capital used a mix of aerobic digestion, lime stabilization and composting. That required significant energy for aeration and costly trucking of
